Regulation of Dendrobium Polysaccharides on Proliferation and Oxidative Stress of Human Umbilical Vein Endothelial Cells in the High Glucose Environment.

Yajia Li,Qiangxiang Li,Meilan Shi,Ziqin Cao,Yanfei Huang,Limin Jia,Almudena G Mez Hern Ndez

doi:10.1155/2021/6685055

Abstract

Backgrounds Polysaccharides of Dendrobium candidum (PDC) showed a strong antioxidant effect on islet cells while the effects of PDC on human umbilical vein endothelial cells (HUVECs) under the high glucose condition remain unclear. Material and Method. HUVECs were incubated with high glucose (33.3 mmol/L) for 48 hours to induce injury, and cells were treated with PDC (100, 200, and 400 μg/mL) for 48 hours. The tetrazolium blue colorimetric (MTT) assay was used to detect cell proliferation, superoxide dismutase (SOD), and nitric oxide (NO) content in cell supernatants. Flow cytometry was used to detect reactive oxygen species (ROS) and calcium levels. Results (1) Compared with the control group, the proliferation of HUVECs cells in the high glucose (33.3 mmol/L) group decreased (P < 0.05). The intracellular calcium ion concentration and the intracellular ROS level increased (P < 0.01 and P < 0.05). SOD activity and the level of NO in the culture medium were reduced (P <0.05). (2) Compared with the control group, PDC (50, 100, 200, 400, and 800 μg/mL) did not significantly affect the cell proliferation of HUVECs (P > 0.05). (3) Compared with the high glucose group, the HUVEC cell viability of the high glucose + PDC (100, 200, and 400 μg/mL) group increased while the intracellular calcium ion concentration decreased in a concentration-dependent manner (P < 0.05). Intracellular ROS levels were reduced, while SOD activity and the level of NO in culture fluids increased (P < 0.05). Conclusion PDC can promote the proliferation of HUVECs in the high glucose environment by reducing oxidative stress injury of HUVECs induced by high glucose.

Highlights

The major chronic complications of diabetes involve the diseases of heart, eye, kidney, foot, and neuropathy, all related to vascular injury [1, 2]
It has been reported that the vascular endothelium-dependent vasodilation function decreases, blood flow velocity decreases, and the vasodilation function is negatively correlated with blood glucose concentration in normal subjects after glucose load, suggesting that high concentrations of glucose can induce the abnormality function of the vascular endothelial’s cell
To evaluate the effect of polysaccharides of Dendrobium candidum (PDC) on the free radicals produced by endothelial cells caused by high glucose, we measured the content of superoxide dismutase (SOD) in the culture medium by colorimetry and the intracellular reactive oxygen species (ROS) level by flow cytometry, which is the most commonly used method of free radical generating ability

Summary

Introduction

The major chronic complications of diabetes (diabetes mellitus, DM) involve the diseases of heart, eye, kidney, foot, and neuropathy, all related to vascular injury [1, 2]. Its role in the chronic pathogenesis of diabetes is direct cytotoxic damage and can act as an important intracellular messenger to activate signaling pathways, directly leading to tissue and cell damage [3, 4]. Previous studies have confirmed that increased reactive oxygen species (ROS) production can lead to decreased endothelial cell survival, and the induction of endothelial cell damage is related to increased. Journal of Diabetes Research intracellular free calcium and activation of ROS [1, 5, 6]. Intracellular levels of reactive ROS and free calcium can contribute to dysfunction and progressive loss of beta cells and thereby to diabetes mellitus. As an antioxidant enzyme in mitochondria, superoxide dismutase (SOD) plays an important role in combating oxidative damage. Studies have shown that PDC has a strong antioxidant effect in vitro, which can inhibit islet cell apoptosis and necrosis, protect islet cells, resist calcium overload, and protect and repair cells [10,11,12]

Methods

Results

Conclusion